Women with increased levels of Müllerian inhibiting substance (MIS) may be at a greater risk for breast cancer, according to researchers from the Fox Chase Cancer Center. MIS is known to regulate in utero sexual differentiation in boys.
The study was published online in the Journal of the National Cancer Institute October 9 in a paper titled “Prospective Case—Control Study of Serum Müllerian Inhibiting Substance and Breast Cancer Risk.”
MIS is a member of the transforming growth factor ß family of growth and differentiation factors that inhibits elongation and branching of mammary ducts. It has been shown to inhibit mammary tumor growth in vitro and in animal models.
Joanne F. Dorgan, Ph.D., and colleagues set out to determine whether serum MIS levels are associated with breast cancer risk. They conducted a prospective case-control study of 309 participants who were registered in the Columbia, Missouri Serum Bank. Blood samples were donated by women with in situ or invasive breast cancer who, at the time of donation, were free of cancer.
Each of 105 breast cancer patients was matched to two control subjects. MIS was measured in serum using an enzyme-linked immunosorbent assay. Estradiol and testosterone concentrations were quantified by using specific radioimmunoassays.
Researchers found that increasing MIS serum concentrations were associated with heightened breast cancer risk in this population. While they believe this could be a good biomarker to determine risk, they point to the need for further confirmatory studies.